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1.
黄孢原毛平革菌菌丝球对Pb2+的动态吸附及其洗脱   总被引:4,自引:0,他引:4  
考察了黄孢原毛平革菌菌丝球对铅离子的动态吸附及其洗脱性能.实验结果表明,流速、温度、溶液pH值和初始浓度等因素对动态吸附有很大影响,饱和吸附量为20.19mg.g-1,比同样条件下的静态饱和吸附量(23.96mg.g-1)稍低.洗脱液流速和洗脱温度对洗脱速率有较大影响,洗脱率在90%以上(最高可达97.16%).  相似文献   

2.
选择8种大孔吸附树脂,比较其对莲房黄酮的吸附和解吸附效果.在静态吸附试验的基础上,筛选出AB-8树脂进行动态吸附试验.实验结果表明,大孔吸附树脂AB-8对莲房黄酮的最佳层析条件为:样液总黄酮液浓度为1.5mg·mL-1,上样流速3BV/h,调节样液pH为3.5上样,以70%的乙醇浓度洗脱,洗脱流速2BV/h.  相似文献   

3.
通过比较5种吸附树脂对柚皮甙的吸附能力,选择了对柚皮甙吸附能力较强,且容易洗脱的吸附树脂X-5,实现了柚皮甙的吸附分离.研究了提取液浓度、pH值、流速等因素对柚皮甙在该树脂上吸附的影响,同时考察了解吸时洗脱剂浓度、pH值、流速等因素对柚皮甙在吸附树脂上解吸的影响.研究结果表明:柚皮甙在X-5大孔吸附树脂的吸附行为可以用Langmuir方程进行描述;当提取液质量浓度为2.7 g/L时,树脂具有最大饱和吸附容量32.6 mg/g;pH值对其吸附影响较弱;当每小时通过的溶剂体积为树脂体积的2倍时,动态吸附时动态饱和吸附容量为23.8 mg/g;pH约为10、体积分数为60%的乙醇水溶液为最佳洗脱剂;当每小时通过的洗脱剂体积为树脂体积的1~2倍时,洗脱率可达85%以上.  相似文献   

4.
X-5树脂吸附分离海边月见草叶总黄酮的影响因素   总被引:2,自引:1,他引:2  
采用3种大孔吸附树脂对海边月见草叶总黄酮进行吸附纯化,筛选出适宜的树脂X-5,考察了原液质量浓度、pH值、温度、树脂用量等因素对该树脂静态吸附的影响,以及洗脱剂乙醇体积分数对静态解吸效果的影响.结果表明:X-5树脂对海边月见草叶总黄酮有良好的吸附纯化性能,当原液质量浓度为1.250m g.mL-1时,树脂达饱和吸附量12.08 m g.g-1(湿质量);在室温、振荡条件下,提取液pH值4.0~4.5时,树脂具有较好的吸附效果;而适宜的洗脱剂为体积分数50%~70%的乙醇溶液,70%乙醇的解吸率为71.27%.  相似文献   

5.
选择8种大孔吸附树脂,比较其对莲房黄酮的吸附和解吸附效果。在静态吸附试验的基础上,筛选出AB-8树脂进行动态吸附试验。实验结果表明,大孔吸附树脂AB-8对莲房黄酮的最佳层析条件为:样液总黄酮液浓度为1.5mg.mL-1,上样流速3BV/h,调节样液pH为3.5上样,以70%的乙醇浓度洗脱,洗脱流速2BV/h。  相似文献   

6.
利用D101大孔吸附树脂对羟基钴胺素的吸附与洗脱性能进行了研究.通过紫外分光光度计和高效液相色谱检测其浓度:树脂静态饱和吸附量为25.31mg/g湿树脂,动态泄漏吸附量为6.22mg/g湿树脂.此外,还考察了洗脱剂乙醇的浓度对于解吸的影响,确定60%的乙醇溶液可以达到最佳的洗脱效果.  相似文献   

7.
改性凹凸棒粘土对水溶液中铜离子吸附性能的研究   总被引:1,自引:0,他引:1  
研究了改性凹凸棒粘土对水溶液中铜离子的吸附规律.结果表明,5%HCl酸活化和400℃热活化的凹凸棒粘土具有很好的吸附性能,粘土添加量为2%时,铜离子的最高去除率分别达到88.1%和90.4%,铜离子的平衡浓度为100 mg·L-1时,粘土的吸附容量分别约为35 mg·g-1和37 mg·g-1.  相似文献   

8.
竹炭对水溶液中Cd(Ⅱ)的吸附研究   总被引:5,自引:1,他引:4  
研究了竹炭对溶液中Cd (Ⅱ) 的吸附行为.考察了酸处理、pH值、竹碳与溶液的接触时间、投料量、吸附温度和Cd (Ⅱ)的初始浓度对吸附的影响.结果表明竹炭对镉离子的吸附是放热过程,并且符合Freundlich吸附模型,在初始浓度为15 mg·L-1、最佳酸度及287K条件下,未经处理的竹炭饱和吸附量达到11.0 mg·g-1,增加竹碳的用量,镉离子吸附率可达99%以上.  相似文献   

9.
通过研究大孔吸附树脂分离纯化柚皮总黄酮的工艺,为柚皮总黄酮的工业化生产提供实验依据。本文以广东产柚皮为原料,以柚皮总黄酮含量及回收率等为考察指标,选用大孔吸附树脂对柚皮总黄酮进行分离纯化,分别采用静态试验、动态试验等分别考察大孔树脂对柚皮总黄酮的分离纯化效果及影响因素。结果表明,D101型大孔吸附树脂对柚皮总黄酮静态饱和比吸附量为63.76mg.g-1(干树脂),洗脱率99.37%,纯度在51.56%以上,是实验树脂中分离纯化柚皮总黄酮的最佳大孔吸附树脂。因此采用本法分离纯化柚皮总黄酮是稳定、高效的,可进一步推广应用于工业化生产。  相似文献   

10.
考察了大孔树脂对紫苏茎提取液中总黄酮的吸附性能,优化了吸附工艺参数。首先对D-101、AB-8、DM130、ADS-7和ADS-17共5种大孔树脂的静态吸附量和解析率进行了实验,选择AB-8为最佳吸附树脂;静态吸附表明,3h内吸附即可达到平衡。还考察了上样速率、上样质量浓度、洗脱液乙醇质量分数和洗脱速率对分离的影响,结果表明优化的条件为:上样速率为1BV/h,上样质量浓度为0.15mg/mL,洗脱液乙醇质量分数为70%,洗脱流速为2BV/h。在此条件下,总黄酮洗脱率为93.56%,总黄酮纯度可提高4.5倍。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

13.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

14.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

15.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

16.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

17.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

18.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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